I have a DC a RODC (Both 2016). I configured my RODC DNS server to forward non AD queries (internet queries) to my ISP's DNS. My workstations have the RODC as primary dns server and the DC as secondary. The name resolution works fine but I realized that my domain controller also caches the requests of of my workstations. I checked that RODC have only my ISP's DNS in forwarders.
Now I wonder if DC and RODC synchronize the cache or my RODC do not actually forward the requests to my ISP but to the DC for some reason.
Thank you in advance.